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.executeTakeFirstOrThrow() returns null instead of throwing

See original GitHub issue

Description

When executing a SELECT query with .executeTakeFirstOrThrow(), it returns null if the result set is empty instead of throwing an exception.

Environment

Name	Version
macOS	13.0
Node	16.17.0
npm	8.15.0
Kysely	0.22.0
Kysely Codegen	0.7.4
MySQL	5.7.38
mysql2	2.3.3

Additional Details

Query was verified to return [] with .execute()
Query was verified to return undefined with .executeTakeFirst()
Query was verified to throw a NoResultError exception when the connection details were invalid
Return type from .executeTakeFirstOrThrow() does not reflect the potential for null
Issue occurs when using min and max aggregate functions; potentially others
Query verified to throw a NoResultError when selecting columns without using aggregate functions

Issue Analytics

State:
Created a year ago
Comments:7 (5 by maintainers)

Top GitHub Comments

2reactions

koskimascommented, Oct 25, 2022

Yep, that query always returns one row, even if the set from which max is taken is empty. That’s how SQL works. As mentioned, we can improve by making the aggregated values nullable, but it won’t change this behavior.

2reactions

igalklebanovcommented, Oct 25, 2022

avg, max, min & sum are nullable when they don’t have rows to work with.

In a future release you’ll be able to opt-in to hinting they are nullable, and/or wrap them with coalesce.